The present invention relates to a sampling gas analyzer for analyzing a gas, or particularly effectively, a gas obtained from a living body.
A sampling respiratory gas analyzer is configured so that a gas to be measured is sucked into the interior of the analyzer, and then subjected to a measurement by a sensor in the analyzer. In such an analyzer, there is a fear of an adverse effect that water vapor contained in the gas to be measured condenses, and, when liquid is sucked into the interior of the analyzer, rust or the like occurs.
In order to solve the problem, a mechanism has been proposed in which liquid to be used in a respiratory gas analyzer is separated by separating the liquid by means of surface tension and capillary action, and then guiding the liquid to a cup (see U.S. Pat. No. 4,713,095). According to the apparatus, liquid which is formed by condensing water vapor contained in the gas to be measured can be separated. However, the apparatus has a problem in that, when the cup of the liquid separator does not exist in the direction of gravitational force of a condensing portion in order to receive the liquid produced by condensation, the liquid enters the interior of the apparatus.
In order to solve the problem, furthermore liquid separators incorporating a mechanism which uses a polymer absorbent, and which, when liquid enters the mechanism, performs a sealing function. Each of such separators is characterized in that the use of a polymer absorbent can prevent liquid from entering the interior of the separator (see U.S. Pat. No. 4,924,860 and U.S. Pat. No. 6,923,847). However, each of the liquid separators remains to have a problem in that the function of separating liquid does not normally function unless the cup of the liquid separator exists in the direction of gravitational force of a condensing portion.